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991.
大鼠肝抑素纯化及其生物活性的检测 总被引:3,自引:1,他引:3
用SephadecG-5凝胶过滤层析法,进一步纯化具肝抑素生物活性的大鼠肝蛋白质粗提品,以分离的大鼠再生肝的肝细胞为靶细胞,体外检测各洗脱峰浓缩物对肝细胞增殖的制率结果证明,E峰浓缩物的抑制作用最强,其活性比为粗提品的20倍,SDS聚丙烯酰胺电泳图及蛋白质迁移率测定表明,该浓缩物的主要成分为分子量13.5kD的多肽。本研究对大鼠肝抑素做了初步纯化,验证了该物质在肝再生中起重要调控作用的生物效应。 相似文献
992.
A genetic linkage map for zebrafish: comparative analysis and localization of genes and expressed sequences 下载免费PDF全文
Gates MA Kim L Egan ES Cardozo T Sirotkin HI Dougan ST Lashkari D Abagyan R Schier AF Talbot WS 《Genome research》1999,9(4):334-347
Genetic screens in zebrafish (Danio rerio) have isolated mutations in hundreds of genes with essential functions. To facilitate the identification of candidate genes for these mutations, we have genetically mapped 104 genes and expressed sequence tags by scoring single-strand conformational polymorphisms in a panel of haploid siblings. To integrate this map with existing genetic maps, we also scored 275 previously mapped genes, microsatellites, and sequence-tagged sites in the same haploid panel. Systematic phylogenetic analysis defined likely mammalian orthologs of mapped zebrafish genes, and comparison of map positions in zebrafish and mammals identified significant conservation of synteny. This comparative analysis also identified pairs of zebrafish genes that appear to be orthologous to single mammalian genes, suggesting that these genes arose in a genome duplication that occurred in the teleost lineage after the divergence of fish and mammal ancestors. This comparative map analysis will be useful in predicting the locations of zebrafish genes from mammalian gene maps and in understanding the evolution of the vertebrate genome. 相似文献
993.
Allelic loss in human papillomavirus-positive and -negative vulvar squamous cell carcinomas 下载免费PDF全文
Pinto AP Lin MC Mutter GL Sun D Villa LL Crum CP 《The American journal of pathology》1999,154(4):1009-1015
Vulvar squamous cell carcinoma (VSCC) is a biologically and morphologically diverse disease, consisting of human papillomavirus (HPV)-positive and -negative tumors that differ in their morphological phenotypes and associated vulvar mucosal disorders. This study analyzed the frequencies of allelic loss (loss of heterozygosity (LOH)) in HPV-positive and -negative VSCCs to identify potential targets for the study of preinvasive diseases, to determine whether HPV status influenced patterns of LOH, and to determine whether these patterns differed from HPV-positive tumors of another genital site, cervical squamous cell carcinomas (CSCC). DNA extracted from microdissected archival sections of two index tumors, one each HPV negative and positive, was analyzed for LOH at 65 chromosomal loci. Loci scoring positive with either sample were included in an analysis of 14 additional cases that were also typed for HPV. Frequencies of LOH at loci were computed in a panel of HPV-positive and -negative VSCCs. Twenty-nine loci demonstrated LOH on the initial screen and were used to screen the remaining 14 tumors. High frequencies of LOH were identified, some of which were similar to a prior karyotypic study (3p, 5q, 8p, 10q, 15q, 18q, and 22q) and others of which had not previously been described in VSCC (1q, 2q, 8q, 10p, 11p, 11q, 17p, and 21q). With the exception of 5q and 10p, there were no significant associations between frequency of LOH and HPV status in VSCC. LOH at 3p and 11q were frequent in both VSCC and CSCC; however, allelic losses at several sites, including 5q, 8q, 17p, 21q, and 22q, were much more common in VSCC. VSCCs exhibit a broad range of allelic losses irrespective of HPV status, with high frequencies of LOH on certain chromosomal arms. This suggests that despite their differences in pathogenesis, both HPV-positive and -negative VSCCs share similarities in type and range of genetic losses during their evolution. Whether the different frequencies of LOH observed between VSCC and CSCC are real or reflect differences in stage and/or tumor size remains to be determined by further comparisons. The role of these altered genetic loci in the genesis of preinvasive vulvar mucosal lesions merits additional study. 相似文献
994.
目的观察心理健康对精神分裂症患者认知功能的影响。方法采用入院顺序分层随机法,将120例慢性精神分裂症患者分为研究组(心理健康+奋乃静)和对照组(单用奋乃静)治疗。在治疗前,治疗后4、8、12周末分别以阳性症状和阴性症状量表(PNASS?评定疗效,用韦氏成人智力量表(WAIS—R)、韦氏记忆量表(WMS)和威斯康星卡片分类测验(wCST)评定治疗前后患者认知功能的改变。结果治疗12周后,研究组的言语量表、操作量表、全量表和记忆量表分分别为84.97±3.73、80.41±5.93、83.37±5.81、77.26±13.31;对照组分别为75.41±3.95、72.43±5.56、75.87±5.34、72.15±13.19,两组有显著差异(P〈0.01)。PANSS总分、阴性因子分比治疗前明显降低。结论心理健康治疗对精神分裂症患者认知功能有明显改善。 相似文献
995.
L. B. Kim 《Bulletin of experimental biology and medicine》2008,146(6):680-681
We studied enzyme systems (lactate dehydrogenase) of mitochondria in cerebral nerve cells in experimental encephalopathy developing
after thermal injury. In animals receiving neuromedin at the early terms after injury, the ratio of forward to reverse lactate
dehydrogenase reactions significantly increased over the first day after injury and returned to normal on day 7.
__________
Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 145, No. 6, pp. 626–627, June, 2008 相似文献
996.
Effect of differences in antibody and complement requirements on phagocytic uptake and intracellular killing of "c" protein-positive and -negative strains of type II group B streptococci 总被引:6,自引:5,他引:6 下载免费PDF全文
The influence of antibody and complement on the polymorphonuclear leukocytic uptake and killing of type II group B streptococci (GBS) was examined with 11 adult sera and three type II strains possessing the trypsin-resistant and trypsin-sensitive components (II/TR+TS) of the "c" (formerly Ibc) protein or two type II strains lacking both components (II/no c) of the c protein. All tested sera mediated a greater than 1 log10 reduction in colony-forming units (CFUR) of a type II/no c strain, even in the absence of measurable type-specific antibody (less than 1.08 micrograms/ml), but only 5 of 11 mediated a greater than 1 log10 CFUR of any type II/TR/TS strain, even in the presence of moderate levels of type-specific antibody. The classical pathway of complement activation appeared to be more important than the alternative pathway, and even absorbed or immunoglobulin G (IgG)-depleted serum (IgG, 10 mg/dl) mediated a greater than 1 log10 CFUR without magnesium ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (magnesium EGTA) chelation. Chelation with magnesium EGTA reduced the CFUR in 4 of 11 test sera and greatly reduced the CFUR in absorbed or IgG-depleted sera for type II/no c strains. Despite variation in the phagocytic killing of two representative strains of type II GBS, both strains were well phagocytized, as measured by radiolabeled bacterial uptake or electron microscopy. This study suggested that poorly killed type II/TR+TS GBS were easily phagocytized but apparently resisted intracellular killing. 相似文献
997.
Production of monoclonal antibody to a phenolic glycolipid of Mycobacterium tuberculosis and its use in detection of the antigen in clinical isolates. 下载免费PDF全文
S N Cho J S Shin M Daffe Y Chong S K Kim J D Kim 《Journal of clinical microbiology》1992,30(12):3065-3069
A monoclonal antibody (MAbIII604) specific to phenolic glycolipid Tb (PGL-Tb), a Mycobacterium tuberculosis-specific antigen, was produced and used in the detection of the antigen. MAbIII604 reacted with the PGL-Tb antigen but not with other phenolic glycolipids from Mycobacterium leprae, M. bovis, and M. kansasii, thus indicating the specificity of the monoclonal antibody to PGL-Tb. A dot enzyme-linked immunosorbent assay with MAbIII604 was employed to detect the PGL-Tb antigen in lipids purified from M. tuberculosis clinical isolates. Of 50 isolates, 32 (64.0%) showed clear evidence of the PGL-Tb antigen by the dot enzyme-linked immunosorbent assay, but there were marked variations in the intensities and sizes of spots. This suggests differences in PGL-Tb antigen production among M. tuberculosis strains even when they are grown in the same culture media and conditions. This was most evident from the fact that in only eight (16.0%) of the isolates examined was the PGL-Tb antigen detectable by thin-layer chromatography, which is much less sensitive for the detection of glycolipid antigens. This study shows that monoclonal antibodies specific to PGL-Tb are useful in detecting the antigen in lipid extracts and that there is a marked variation in the PGL-Tb production among M. tuberculosis clinical isolates. 相似文献
998.
Effect of biphenyl dimethyl dicarboxylate on the humoral immunosuppression by ethanol 总被引:3,自引:0,他引:3
Kim JH Mun YJ Chun HJ Jeon KS Kim YO Woo WH 《International journal of immunopharmacology》2000,22(11):905-913
The present study was undertaken to investigate the effect of biphenyl dimethyl dicarboxylate (PMC) on the humoral immunosuppression by ethanol (EtOH) in ICR mice. PMC at a dose of 6 mg/kg was orally administered to mice daily for 28 consecutive days, and the control mice were given vehicle. Mice treated with EtOH were given freely with 20% EtOH instead of water. The results of this study are summarized as follows; a gain of body weight and the relative weights of spleen and liver were significantly increased by combination of PMC and EtOH, as compared with those in mice treated with EtOH alone. Splenic plaque forming cells (PFC) and hemagglutination (HA) titers to sheep red blood cells (SRBC), and the secondary IgG antibody response to bovine serum albumin (BSA) were decreased by the treatment of EtOH alone, then restored to normal level by PMC treatment. The elevations of serum glutamic-pyruvic transaminase (S-GPT) and total protein levels caused by EtOH were reduced to normal level by the combination of PMC and EtOH. In addition, lower serum albumin and A/G ratio were also increased to normal level. These findings indicate that PMC has a protective effect against EtOH-induced humoral immunosuppression. 相似文献
999.
Comparison of major antigenic proteins of six strains of the human granulocytic ehrlichiosis agent by Western immunoblot analysis. 总被引:8,自引:7,他引:8 下载免费PDF全文
N Zhi Y Rikihisa H Y Kim G P Wormser H W Horowitz 《Journal of clinical microbiology》1997,35(10):2606-2611
The etiologic agent of human granulocytic ehrlichiosis (HGE) is an obligate intracellular bacterium. In 1996, blood specimens from 53 patients suspected of having HGE were examined by indirect fluorescent antibody (IFA) testing with the HGE agent no. 13 isolate as the antigen, by nested PCR, and by culture. All patients resided in Westchester County, N.Y. Twelve patient specimens were positive for IFA (titer > or = 1:40). Seven of these were also positive by PCR. Of the seven specimens positive by both IFA testing and PCR, the HGE agent was isolated from four (no. 2, 3, 6, and 11) and continuously cultured in HL-60 cells. These were confirmed as the HGE agent by sequencing of 16S rDNA. Both purified whole-cell organisms and the outer membrane fractions of the new isolates were compared with no. 13 isolate and a tick (USG) isolate by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western immunoblot analysis. No. 11 and 13 isolates had identical SDS-PAGE patterns with respect to 49- and 47-kDa proteins. No. 3 and USG isolates lacked the 47-kDa protein, and no. 6 isolate lacked the 49-kDa protein. Both 49- and 47-kDa bands were absent in no. 2 isolate. Western blot results with seven different sera, including five convalescent-phase sera from these patients, one dog anti-USG isolate, and one horse anti-BDS isolate, showed that all major antigens in six isolates were recognized by all sera. However, the molecular sizes and the numbers of major antigens recognized varied among the six isolates. Overall, HGE agent no. 3, 6, 11, and 13, and USG isolates had similar patterns, with 1 or 2 major antigens with molecular masses of around 49 and 47 kDa. No. 2 isolate was quite distinct in having a major antigen of 43 kDa. This indicates that although these antigenic epitopes are all cross-reactive among strains, the HGE agent has a strain pleomorphism in its major antigenic proteins. The major antigen profiles of the outer membrane protein fractions and of whole organisms of six HGE agent isolates were similar, suggesting that 49- and 47-kDa major antigens are the outer membrane proteins of the HGE agent. 相似文献
1000.
本文报告江苏省淮阴县运南地区方氏家族六代683人的系谱、皮纹学、染色体和ABO血型等遗传学方法的调查与检测,确定属常染色体显性遗传性聋患者137例。经检索这是我国首例显性遗传性聋大家系,亦是国际上的第三例聋人大家系的报告。 相似文献